You made a claim ("It would take an immensely ballsy release engineer to approve switching from GCC to clang even for a modestly sized, mature codebase"); people pointed out counter-examples (Apple and Google); you move the goalposts. Would it have killed you to admit that you were wrong in the post as written?
There is little motivation in commenting unless in the process I can enhance or validate my understanding. Often this naturally means arguing details until out of breath, or my diatribe is so sufficiently beaten back that I'm too exasperated to continue – at which point the topic will sink in, until reiterated at some later date in some later argument – with a level of belief that cannot be attained unless all alternatives have first been eliminated. I'd much rather die fierce yet wrong than live a life shrouded in vagueness.